Mechanisms of thermochemical biomass conversion processes. Part 2: Reactions of gasification

Gasification as a thermochemical process is defined and limited to combustion and pyrolysis. The gasification of biomass is a thermal treatment which results in a high proportion of gaseous products and small quantities of char (solid product) and ash. Biomass gasification technologies have historically been based upon partial oxidation or partial combustion principles, resulting in the production of a hot, dirty, low Btu gas that must be directly ducted into boilers or dryers. In addition to limiting applications and often compounding environmental problems, these technologies are an inefficient source of usable energy. The main objective of the present study is to investigate gasification mechanisms of biomass structural constituents. Complete gasification of biomass involves several sequential and parallel reactions. Most of these reactions are endothermic and must be balanced by partial combustion of gas or an external heat source.